Doubles
2018 Seoul Open Challenger
Final
Champions	Toshihide Matsui Frederik Nielsen
Runners-up	Chen Ti Yi Chu-huan
Score	6–4, 7–6(7–3)
Events
Singles Doubles
← 2017 · Seoul Open Challenger · 2019 →

In the 2018 Seoul Open Challenger Doubles tennis tournament, Hsieh Cheng-peng and Peng Hsien-yin were the defending champions but chose to defend their title with different partners. Hsieh partnered Christopher Rungkat but lost in the quarterfinals to Toshihide Matsui and Frederik Nielsen. Peng partnered Aliaksandr Bury but lost in the semifinals to Chen Ti and Yi Chu-huan.

Matsui and Nielsen won the title after defeating Chen and Yi 6–4, 7–6^(7–3) in the final.

	First round							Quarterfinals							Semifinals							Final
	1	C-p Hsieh C Rungkat	6	3	[10]
	WC	Kim Yu-seob Lim Hyung-chan	4	6	[2]			1	C-p Hsieh C Rungkat	62	1
		T Matsui F Nielsen	6	6					T Matsui F Nielsen	77	6
	WC	Kim Young-seok D-h Lee	4	2												T Matsui F Nielsen	6	3	[15]
	4	M Reid D Sela	1	6	[10]											T Ito M McDonald	4	6	[13]
	LL	M Banes B Ellis	6	3	[8]			4	M Reid D Sela	4	5
		T Ito M McDonald	4	6	[10]				T Ito M McDonald	6	7
	WC	Lim Min-seob Yoon Il-sang	6	3	[2]																		T Matsui F Nielsen	6	77
		R Gonzales J Jung	4	6	[12]																		T Chen C-h Yi	4	63
	Q	Y-s Chung Yo Watanuki	6	2	[10]				R Gonzales J Jung	4	6	[6]
		K Majchrzak L Saville	2	4				3	A Bury H-y Peng	6	1	[10]
	3	A Bury H-y Peng	6	6											3	A Bury H-y Peng	4	64
		D Wu Ze Zhang	6	6												T Chen C-h Yi	6	77
		M Gong Y Uchiyama	2	3					D Wu Ze Zhang	5	2
		T Chen C-h Yi	78	4	[10]				T Chen C-h Yi	7	6
	2	Sa Ratiwatana So Ratiwatana	66	6	[8]

• Main Draw
• Qualifying Draw